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How is a Twix bar like the Earth?

Earth’s Layers

3 Compositional LayersC.M.C.

<1% Earth’s mass

67% Earth’s mass

33% Earth’s mass

Crust

Continental Crust• 30-50 km thick• Less dense• Silicon, aluminum

Oceanic Crust• 10 km thick• More dense• Iron, magnesium,

basalt

Mantle

• A lot of Magnesium• A little silicon and

aluminum• Denser than the

crust• Holds magma that

comes out of volcanoes

Core

• Iron and nickel•Most dense•Extremely hot

Compositional vs. Physical

5 Physical Layers

• Lithosphere• Asthenosphere•Mesosphere• Outer Core• Inner Core

• Laughing• At•My• Omelet,• Interesting!

Lithosphere(Laughing)

•Crust and Upper Mantle•Rigid•Divided into

tectonic plates

Asthenosphere (At)

•Middle Mantle• Soft, plastic-like• Tectonic plates

floats on this

Mesosphere (My)

• Lower Mantle• Strong• Semi-solid (Like caramel)

Outer Core(Omelet)

•Liquid because the inner core is so hot•Reason why

Earth is a giant magnet

Inner Core (Interesting)

•Center of Earth•Solid ball•Dense•EXTREMELY hot!

Why are there layers?

•Heavier elements tend to sink to the core

• Lighter elements rise toward the crust